Method and System for a Time Domain Approach to 4G/LTE-WiFi/BT Coexistence

ABSTRACT

A method and system are provided in which a device that is operable to handle WiFi communication and WiMAX communication may receive downlink medium access protocol (MAP) information in a downlink sub-frame of a WiMAX frame and disable WiFi transmission during a portion of the downlink sub-frame based on the downlink MAP information. The disabled WiFi transmission may be enabled after data within the downlink sub-frame is decoded. The device may also receive uplink MAP information in the downlink sub-frame and may control a clear channel assessment associated with the WiFi transmission based on the uplink MAP information. The MAP information may comprise data or burst profile information and/or one or more physical control messages. A similar time domain approach may be utilized for coexistence between Win and long term evolution (LTE) coexistence, Bluetooth and WiMAX, and Bluetooth and LTE. Frame aggregation may be enabled to alleviate pending WiFi traffic.

CROSS-REFERENCE TO RELATED APPLICATIONS/INCORPORATION BY REFERENCE

This application is a continuation of U.S. application Ser. No.13/024,124, filed Feb. 9, 2011, which claims priority to and makesreference to U.S. Provisional Patent Application Ser. No. 61/308,250filed on Feb. 25, 2010, all of which are incorporated by referenceherein in their entirety.

FIELD OF THE INVENTION

Certain embodiments of the invention relate to interference incommunication systems. More specifically, certain embodiments of theinvention relate to a method and system for a time domain approach to 4GWiMAX/LTE and WiFi/BT coexistence.

BACKGROUND OF THE INVENTION

Personal area networks (PANs), such as WiFi networks and Bluetooth (BT)networks, for example, and fourth generation (4G) networks, such asWorldwide Interoperability for Microwave Access (WiMAX) and Long TermEvolution (LTE), for example, have been gaining popularity because ofthe flexibility, convenience in connectivity, and/or high datathroughput they provide. Devices that support both types of networksneed to enable operation with limited and/or reduced interference.

Further limitations and disadvantages of conventional and traditionalapproaches will become apparent to one of skill in the art, throughcomparison of such systems with the present invention as set forth inthe remainder of the present application with reference to the drawings.

BRIEF SUMMARY OF THE INVENTION

A system and/or method for a time domain approach to 4G WiMAX/LTE andWiFi/BT coexistence, as set forth more completely in the claims.

Various advantages, aspects and novel features of the present invention,as well as details of an illustrated embodiment thereof, will be morefully understood from the following description and drawings.

BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWINGS

FIG. 1A is a diagram that illustrates, an exemplary router that supportscommunication through a 4G network and a WiFi network, in accordancewith an embodiment of the invention.

FIG. 1B is a diagram that illustrates an exemplary device that supportscommunication through a 4G network and a PAN network, in accordance withan embodiment of the invention.

FIG. 2 is a diagram that illustrates WiMAX and WiFi/BT radio spectrum,in connection with an embodiment of the invention.

FIGS. 3A-3C are block diagrams of exemplary 4G and WiFi/BT coexistencesystems, in accordance with embodiments of the invention.

FIG. 4 is a diagram that illustrates an exemplary time domain approachto 4G and WiFi/BT coexistence, in accordance with an embodiment of theinvention.

FIG. 5 is a flow diagram that illustrates exemplary steps for a timedomain approach to 4G and WiFi/BT coexistence, in accordance with, anembodiment of the invention.

FIG. 6 is a flow diagram that illustrates exemplary steps to aggregateuplink transmissions in a 4G and WiFi/BT coexistence system, inaccordance with an embodiment of the invention.

FIG. 7 is a flow diagram that illustrates exemplary steps during WiMAXhandoff scanning in a 4G and WiFi/BT coexistence system, in accordancewith an embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION

Certain embodiments of the invention can be found in a method and systemfor a time domain approach to 4G WiMAX/LTE and WiFi/BT coexistence.Various embodiments of the invention provide a device that is operableto handle WiFi communication and WiMAX communication. Such device mayreceive downlink medium access protocol (MAP) information in a downlinksub-frame of a WiMAX frame and may disable WiFi transmission during aportion of the downlink sub-frame based on the received downlink MAPinformation. The disabled WiFi transmission may be enabled after datawithin the downlink sub-frame is decoded. The device may also receiveuplink MAP information in the downlink sub-frame and may control a clearchannel assessment (CCA) associated with the WiFi transmission based onthe received uplink MAP information. The MAP information in the downlinksub-frame may comprise a profile of the data or burst information and/orone or more physical control messages associated with both sub-frames inthe WiMAX frame. In an LTE system, the Packet Data Control Channel(PDCCH) and the Physical Uplink Control Channel (PUCCH) may be utilizedto inform the terminal about downlink and uplink transmissions. Asimilar time domain approach may be utilized for WiFi and time-divisionduplex LTE (TDD-LTE) coexistence. In case of frequency-division duplexLTE (FDD-LTE), the approach is applicable to WiFi/BT coexistence withcertain extensions as described below. Moreover, frame aggregation maybe enabled to alleviate pending WiFi transmission traffic.

FIG. 1A is a diagram that illustrates an exemplary router that supportscommunication through a 4G network and a WiFi network, in accordancewith an embodiment of the invention. Referring to FIG. 1A, there isshown a 4G network 130 and a WiFi network 140. In some embodiments ofthe invention, the 4G network 130 may be a WiMAX network such as amobile WiMAX network or a WirelessMAN-Advanced network, for example. Inother embodiments of the invention, the 4G network 130 may be an LTEnetwork, including advanced versions of LTE such as an LTE Advancednetwork, for example. The LTE network may operate as a TDD-LTE networkor as an FDD-LTE network. In yet another embodiment of the invention,the 4G network 130 may support WiMAX communication and LTE communicationat the same time.

A base station 110 and a router 100 are also shown as part of the 4Gnetwork 130. The base station 110 and the router 100 may communicatethrough a link 132 that enables 4 G communication in a downlinkdirection and/or in an uplink direction. The router 100 and a userdevice 120 are shown, as part of the WiFi network 140. The router 100and the user device 120 may communicate through a link 142 that enablesWiFi communication in a downlink direction and/or in an uplinkdirection.

The router 100 may be a mobile router, for example. The router 100 maycomprise suitable logic, circuitry, interfaces and/or code that may beoperable to limit and/or reduce the interference that may occur byhaving 4G and WiFi coexistent operations. The router 100 may be operableto communicate such that the reception of WiMAX or LTE signals from thebase station 110 is not affected by the transmission of WiFi signals tothe user device 120. In this regard, the router 100 may enable about a25 dB isolation between the antenna(s) used for 4 G communication andthe antenna(s) used for WiFi communication. The router 100 may supportother types of communication as well. For example, the router 100 maysupport communication through wireless local area networks that arebased on the IEEE 802.11 standards, through other cellular wirelessnetworks, and/or through personal area network technologies.

The user device 120 may comprise suitable logic, circuitry, interfacesand/or code that may be operable to support WiFi communication.Moreover, the user device 120 may support communication with one or morenearby devices (not shown) through personal area network technologiessuch as infrared data association (IrDA), Bluetooth, ultra-wideband(UWB), Z-Wave and ZigBee, for example. The user device 120 may be, forexample, a smartphone, a laptop, a tablet, or other like mobile and/orportable computing device. The user device 120 may also be referred toas a station.

In operation, downlink traffic may flow from the base station 110 to therouter 100 via the link 132 in the 4G network 130. The downlink trafficmay then be communicated by the router 100 to the user device 120 viathe link 142 in the WiFi network 140. In such an instance, since similardownlink traffic may flow in both networks, the downlink traffic in the4G network 130 may be said to be correlated with the downlink traffic inthe WiFi network 140.

Similarly, uplink traffic may flow from the user device 120 to therouter 100 via the link 142 in the WiFi network 140. The uplink trafficmay then be communicated by the router 100 to the base station 110 viathe link 132 in the 4G network 130. In such an instance, since similaruplink traffic may flow in both networks, the uplink traffic in the WiFinetwork 140 may be said to be correlated with the uplink traffic in the4G network 130.

In one embodiment of the invention, when the 4G network 130 is a WiMAXnetwork and a single station is considered in the WiFi network 140, theWiMAX/WiFi downlink throughput may be able to support about 13megabits-per-second (Mb/s) for Transmission Control Protocol (TCP) whilethe WiMAX/WiFi uplink throughput may be able to support about 4 Mb/s forTCP.

In another embodiment of the invention, when the 4G network 130 is anLTE network and a single station is considered in the WiFi network 140,the LTE/WiFi downlink throughput may be able to support about 50 Mb/sfor TCP while the LTE/WiFi uplink throughput may be able to supportabout 10 Mb/s for TCP.

FIG. 1B is a diagram that illustrates an exemplary device that supportscommunication through a 4G network and a PAN network, in accordance withan embodiment of the invention. Referring to FIG. 1B, there is shown the4G network 130, the base station 110, the user device 120, a personalarea network 150, and a coexistence device 160. The personal areanetwork 150 may support one or more of IrDA, Bluetooth, UWB, Z-Wave, andZigBee technologies, which may also be supported by the user device 120.

The coexistence device 160 may comprise suitable logic, circuitry, code,and/or interfaces that may be operable to enable traffic between the 4Gnetwork 130 and the personal area network 150. In this regard, thecoexistence device 160 may be operable to limit and/or reduce theinterference that may occur by having 4G and personal area networktechnologies coexist. In some embodiments of the invention, thecoexistence device 160 may be a router such as the router 100 describedabove. In other embodiments of the invention, the coexistence device 160may be a mobile computing device, such as a smartphone, for example.

The coexistence device 160 may communicate with the base station 110through a link 152 that may be substantially similar to the link 132described above. The coexistence device 160 and the user device 120 maycommunicate through a link 154 that enables IrDA, Bluetooth, UWB,Z-Wave, and/or ZigBee communication in a downlink direction and/or in anuplink direction. In some instances, the user device 120 may refer to aperipheral device such as a headset and/or printer, for example.

When the personal area network 150 supports Bluetooth and/or ZigBeecommunication, for example, the traffic in the personal area network 150and the traffic in the 4G network 130 may be correlated.

FIG. 2 is a diagram that illustrates WiMAX and WiFi/BT radio spectrum,in connection with an embodiment of the invention. Referring to FIG. 2,there is shown a portion of the radio spectrum 200 that may be utilizedfor an unlicensed Industrial, Scientific, and Medical (ISM) band. Theunlicensed ISM band is positioned between portions of the radio spectrum210 and 212 that may be utilized for WiMAX communication. For example,the unlicensed ISM band may comprise those frequencies between 2.401 GHzand 2.473 GHz, while frequencies above 2.496 GHz and below 2.36 GHz maybe utilized for WiMAX communication. In some instances, the same portionof the radio spectrum utilized for WiMAX communication may support LTEcommunication.

The frequencies in the unlicensed ISM band may be utilized for WiFiand/or Bluetooth communication. For WiFi applications in North America,11 different channels 220, each having a 22 MHz bandwidth, may beutilized as shown in FIG. 2. Bluetooth comprises 79 channels in the ISMband, each channel having a 1 MHz bandwidth. Bluetooth channel hoppingoperates at a rate of 1600 times per second.

The close frequency separation that exists between the WiMAX radiospectrum and the unlicensed ISM band may result in mutual interferenceamong wireless technologies that utilize such close frequencies.Accordingly, a router, such as the router 100 described above withrespect to FIG. 1A, may need to enable operations that limit and/orreduce interference.

In accordance with an embodiment of the invention, the router 100 mayperform a time domain approach to 4G and WiFi coexistence to limitand/or reduce interference by enabling and/or disabling WiFicommunication based on information received through one or more WiMAXand/or LTE frames. Similarly, the coexistence device 160 may perform atime domain approach to 4G and Bluetooth coexistence to limit and/orreduce interference by enabling and/or disabling Bluetooth communicationbased on information received through one or more WiMAX and/or LTEframes.

FIGS. 3A-3B are block diagrams of exemplary 4G and WiFi/BT coexistencesystems, in accordance with embodiments of the invention. Referring toFIG. 3A, there is shown a 4G and WiFi/BT coexistence system 300 that maycomprise a WiFi/BT modem 310, a 4G modem 320, a WiFi/BT front end 330,and a 4G front end 340. In some embodiments of the invention, thevarious components shown in FIG. 3A may be implemented in the router100, in the coexistence device 160, or in other like device.

The WiFi/BT modem 310 may comprise suitable logic, circuitry, code,and/or interfaces that may operable to handle WiFi and/or Bluetoothcommunication. In this regard, the WiFi/BT modem 310 may be operable toprocess data, control signals, and/or other information associated withWiFi and/or Bluetooth communication. In some embodiments of theinvention, the WiFi/BT modem 310 may be operable to perform routingoperations. The WiFi/BT modem 310 may be implemented as an integratedcircuit having a single substrate and disposed in a single package. Insome embodiments of the invention, the WiFi/BT modem 310 may supportonly one of WiFi communication and Bluetooth communication. In otherembodiments of the invention, the WiFi/BT modem 310 may support both ofWiFi communication and Bluetooth communication.

The WiFi/BT modem 310 may be operable to receive uplink traffic from auser device, such as the user device 120, for example. The uplinktraffic may be received by the WiFi/BT modem 310 through the WiFi/BTfront end 330 and signals 322. The WiFi/BT modem 310 may communicate theuplink traffic to the 4G modem 320 when such traffic is intended to becommunicated to the base station 110. The transfer of the uplink trafficbetween the two modems may occur via one or more buses (not shown) thatmay be controlled by one or more processors (not shown) usinginformation such as queue depths, delay, and/or throughput.

The WiFi/BT modem 310 may be operable to receive downlink traffic fromthe 4G modem 320. Such downlink traffic may have been received by the 4Gmodem 320 from the base station 110, for example, and may be intendedfor the user device 120. The transfer of the downlink traffic betweenthe two modems may occur via one or more buses (not shown) that may becontrolled by one or more processors (not shown) using information suchas queue depths, delay, and/or throughput. The downlink traffic may becommunicated to the user device 120 through the WiFi/BT front end 330and signals 322.

The 4G modem 320 may comprise suitable logic, circuitry, code, and/orinterfaces that may operable to handle 4 G communication such as WiMAXcommunication and/or LTE communication, for example. In this regard, the4G modem 320 may be operable to process data, control signals, and/orother information associated with WiMAX communication and/or LTEcommunication. In some embodiments of the invention, the 4G modem 320may be operable to perform routing operations. The 4G modem 320 may beimplemented as an integrated circuit having a single substrate anddisposed in a single package.

The 4G modem 320 may be operable to receive downlink traffic from a basestation, such as the base station 110, for example. The downlink trafficmay be received by the 4G modem 320 through the 4G front end 340 andsignals 332. The 4G modem 320 may communicate the downlink traffic tothe WiFi/BT modem 310 when such traffic is intended to be communicatedto the user device 120. The transfer of the downlink traffic between thetwo modems may occur via one or more buses (not shown) that may becontrolled by one or more processors (not shown) using information suchas queue depths, delay, and/or throughput.

The 4G modem 320 may be operable to receive uplink traffic from theWiFi/BT modem 310. Such uplink traffic may have been received by theWiFi/BT modem 310 from the user device 120, for example, and may beintended for the base station 110. The transfer of the uplink trafficbetween the two modems may occur via one or more buses (not shown) thatmay be controlled by one or more processors (not shown) usinginformation such as queue depths, delay, and/or throughput. The uplinktraffic may be communicated to the base station 110 through the 4G frontend 340 and signals 332.

The WiFi/BT front end 330 may comprise suitable logic, circuitry, code,and/or interfaces that may be operable to transmit and/or receive WiFiand/or Bluetooth signals over the unlicensed ISM band. The WiFi/BT frontend 330 may be operable to perform various operations on WiFi and/orBluetooth signals such as filtering, amplifying, mixing, upconverting,and/or downconverting, for example.

The 4G front end 340 may comprise suitable logic, circuitry, code,and/or interfaces that may be operable to transmit and/or receive 4Gsignals in portions of the radio spectrum that are neat the unlicensedISM band. The 4G front end 340 may be operable to perform variousoperations on 4G signals such as filtering, amplifying, mixing,upconverting, and/or downconverting, for example. The 4G front end 340may be operable to perform multiple-input-multiple-output (MIMO)operations associated with the transmission and/or reception of 4Gsignals. In this regard, the 4G front end 340 may utilize multipleantennas for carrying out the MIMO operations.

In operation, the 4G and WiFi/BT coexistence system 300 may utilize atime domain approach to limit and/or reduce interference in 4G and WiFicoexistence by enabling and/or disabling WiFi communication based oninformation received through one or more WiMAX and/or LTE frames.Similarly, the 4G and WiFi/BT coexistence system 300 may utilize a timedomain approach to limit and/or reduce interference in 4G and Bluetoothcoexistence by enabling and/or disabling Bluetooth communication basedon information received through one or more WiMAX and/or LTE frames.

FIG. 3A also shows a high-level discrete signaling mechanism between the4G modem 320 and the WiFi/BT modem 310 that may be utilized to limitand/or reduce interference in the 4G and WiFi/BT coexistence system 300.The signaling mechanism shown in FIG. 3A is based on a 3-wire interface,however, fewer or more wires and/or signals may also be utilized toimplement the signaling mechanism.

A signal 334, RX_Active, may Le asserted by the 4G modem 320 and theasserted signal may be communicated to the WiFi/BT modem 310 to indicatethat the 4G modem 320 is receiving information and that the WiFi/BTmodem 310 is to stop or terminate any WiFi and/or Bluetoothtransmissions and/or related baseband processing. The asserted RX_Activesignal 334 may also be communicated to the WiFi/BT front end 330 todisable a power amplifier (PA) 350. By disabling both the basebandprocessing and the PA 350 through the asserted RX_Active signal 334, the4G modem 320 may receive 4G signals without the likelihood ofinterference from WiFi and/or BT transmissions. Additional informationregarding the RX_Active signal 334 is provided below with respect toFIG. 4.

A signal 336, TX_Active, may be asserted by the 4G modem 320 and theasserted signal may be communicated to the WiFi/BT modem 310 to indicatethat the 4G modem 320 is transmitting information and that the WiFi/BTmodem 310 may transmit or receive WiFi and/or Bluetooth signals. TheTX_Active signal 336 may be utilized by the WiFi/BT modem 310 inconnection with a CCA operation in WiFi to determine that the energythat is being detected by the WiFi/BT modem 310 in the physical mediumis associated with the 4G transmission and not with some other source.By having knowledge that the energy being detected is from the 4G modem320, the WiFi/BT′modem 310 need not limit its operation when such energyis detected. Additional information regarding the TX_Active signal 336is provided below with respect to FIG. 4.

A signal 338, WiFi_Data_Pending, may be asserted by the WiFi/BT modem310 and the asserted signal may be communicated to the 4G modem 320 toindicate that there is a backup in WiFi and/or Bluetooth transmissions.The 4G modem 320 may utilize this information to modify the bandwidthallocated by the base station to alleviate the pending WiFitransmissions in the WiFi/BT modem 310. Additional information regardingthe WiFi_Data_Pending signal 338 is provided below with respect to FIG.6.

Referring to FIG. 3B, there is shown a 4G and WiFi/BT coexistence system350 that may comprise a 4G-WiFi/BT modem 360, the WiFi/BT front end 330,and the 4G front end 340. In some embodiments of the invention, thevarious components shown in FIG. 3B may be implemented in the router100, in the coexistence device 160, or other like device.

The 4G-WiFi/BT modem 360 may be operable to perform the operations ofthe WiFi/BT modem 310 and of the 4G modem 320 described above. Inaddition, the functionality and/or operation associated with high-leveldiscrete signaling mechanism described above may be implemented withinthe 4G-WiFi/BT modem 360. In this regard, transmit and/or receive bufferinformation may be utilized by the 4G-WiFi/BT modem 360 to generate theappropriate signaling and/or equivalent functionality to limitinterference between 4G and WiFi communications and/or between 4G andBluetooth communications. Part of the signaling operation may comprisegenerating a signal 354 to disable the PA 350 in the WiFi/BT front end330 when appropriate. The 4G-WiFi/BT modem 360 may be implemented as anintegrated circuit having a single substrate and disposed in a singlepackage. In some embodiments of the invention, the 4G-WiFi/BT modem 360may support only one of WiFi communication and Bluetooth communication.In other embodiments of the invention, the 4G-WiFi/BT modem 360 maysupport both of WiFi communication and Bluetooth communication.

Referring to FIG. 3C, there is shown a 4G and WiFi/BT coexistence system370 that may comprise the 4G-WiFi/BT modem 360, the WiFi/BT front end330, and the 4G front end 340. In some embodiments of the invention, the4G and WiFi/BT coexistence system 370 shown in FIG. 3C may beimplemented in the router 100, in the coexistence device 160, or otherlike device. The 4G and WiFi/BT coexistence system 370 may beimplemented as an integrated circuit having a single substrate anddisposed in a single package.

FIG. 4 is a diagram that illustrates an exemplary time domain approachto 4G and WiFi/BT coexistence, in accordance with an embodiment of theinvention. Referring to FIG. 4, there are shown two consecutive WiMAXframes, Frame N and Frame N+1, which may be associated with WiMAXcommunication in a system such as the 4G and WiFi/BT coexistence system300, for example.

The first frame, Frame N, may comprise a downlink (DL) sub-frame and anuplink (UL) sub-frame. The second frame, Frame N+1, may also comprise aDL sub-frame and a UL sub-frame. The DL sub-frames in both frames mayhave a substantially similar structure. The UL sub-frames in both framesmay also have a substantially similar structure. For example, both DLsub-frames may comprise 29 symbols and have a duration of about 3milliseconds (ms). The DL sub-frames may comprise a preamble 408,downlink and uplink (DL/UL) medium access protocol (MAP) information410, and DL data protocol data units (PDUs) 412. The DL data PDUs 412may be structured to support multiple downlink data bursts. The MAPinformation may comprise a downlink burst profile, an uplink burstprofile, and one or more physical layer control messages.

Both UL sub-frames may comprise 18 symbols and may have a duration ofabout 2 ms. The UL sub-frames may comprise ranging information 422,Channel Quality Indicator Channel (CQICH) information 424, HybridAutomatic Repeat Request (HARD) information 426, and an UL data zone420. The UL data zone 420 may be structured to support multiple uplinkdata bursts.

In operation, the 4G modem 320 in the 4G and WiFi/BT coexistence system300 may begin processing the DL sub-frame of Frame N. In this regard,the RXActive signal 334 may be asserted by the 4G modem 320 at the startof the DL sub-frame processing, that is, at time instant T0. The 4Gmodem 320 may determine, based on the downlink MAP information in theDL/UL MAP information 410, whether there is any data that needs to bedecoded in the DL data PDUs 412. In this example, data is available tobe decoded and the 4G modem 320 maintains the RX_Active signal 334asserted until the decoding is completed at time instant T1. While theDL sub-frame of Frame N ends at time instant T2, the RX_Active signal334 is maintained deasserted by the 4G modem 320 until the start of theDL sub-frame of Frame N+1 at time instant T6.

In response to the assertion of the RX_Active signal 334 by the 4G modem320, the WiFi/BT modem 310 in the 4G and WiFi coexistence system 300 maynot transmit WiFi between time instants T0 and T1. Once the RX_Activesignal 334 is deasserted, the WiFi/BT modem 310 may transmit and/orreceive WiFi until time instant T6.

At time instant T3, the 4G modem 320 may begin processing the ULsub-frame of Frame N. In this regard, the TX_Active signal 336 may beasserted by the 4G modem 320 at the start of the UL sub-frameprocessing. The 4G modem 320 may determine, based on the uplink MAPinformation in the DL/UL MAP information 410, whether there is any datathat needs to be decoded in the UL data zone 420. In this example, nodata is available to be decoded and the 4G modem 320 maintains theTX_Active signal 336 asserted until the processing of controlinformation is completed at time instant T4. While the UL sub-frame ofFrame N ends at time instant T5, the TX_Active signal 336 is maintaineddeasserted by the 4G modem 320 until the start of the UL sub-frame ofFrame N+1 at time instant T9.

In response to the assertion of the TX_Active signal 336 by the 4G modem320 during time instants T3 and T4, the WiFi/BT modem 310 may determine,in connection with a CCA operation, that the energy detected in thephysical medium is that of the WiMAX transmission and that the physicalmedium may be available for WiFi communication.

At time instant T6, the 4G modem 320 may begin processing the DLsub-frame of Frame N+1. In this regard, the RX_Active signal 334 may beasserted by the 4G modem 320 at the start of the DL sub-frameprocessing. The 4G modem 320 may determine, based on the downlink MAPinformation in the DL/UL MAP information 410, whether there is any datathat needs to be decoded in the DL data PDUs 412. In this example, thereis no data that needs to be decoded and the 4G modem 320 maintains theRX_Active signal 334 asserted until the reading of the DL/UL MAPinformation 410 is completed at time instant T7. While the DL sub-frameof Frame N ends at time instant T8, the RX_Active signal 334 ismaintained deasserted by the 4G modem 320 until the end of the ULsub-frame of Frame N+1 at time instant T10.

In response to the assertion of the RX_Active signal 334 by the 4G modem320, the WiFi/BT modem 310 may not transmit WiFi between time instantsT6 and T7. Once the RX_Active signal 334 is deasserted, the WiFi/BTmodem 310 may transmit and/or receive WiFi until time instant T10.

At time instant T8, the 4G modem 320 may begin processing the ULsub-frame of Frame N+1. In this regard, the TX_Active signal 336 may beasserted by the 4G modem 320 at the start of the UL sub-frameprocessing. The 4G modem 320 may determine, based on the uplink MAPinformation in the DL/UL MAP information 410, whether there is any datathat needs to be decoded in the UL data zone 420. In this example, thereis data available to be decoded and the 4G modem 320 maintains theTX_Active signal 336 asserted until the data decoding is completed attime instant T10.

In response to the assertion of the TX_Active signal 336 by the 4G modem320 during time instants T9 and T10, the WiFi/BT modem 310 maydetermine, in correction with a CCA operation, that the energy detectedin the physical medium is that of the WiMAX transmission and that thephysical medium may be available for WiFi communication.

While the time domain approach to 4G and WiFi/BT coexistence in FIG. 4is described in connection with WiMAX communication, the invention neednot be so limited. For example, a similar approach may be utilized whenTDD-LTE is utilized for 4 G communication. In such instances, processingof the DL sub-frames and the UL sub-frames may determine when to assertand deassert the RX_Active signal 334 and/or the TX_Active signal 336,for example. A similar approach may also be utilized when the 4 Gcommunication is based on FDD-LTE.

While the time domain approach to 4G and WiFi/BT coexistence in FIG. 4is described in connection with the high-level discrete signalingmechanism of FIG. 3A, the invention need not be so limited. For example,a similar mechanism or other signaling mechanisms may be utilized toprovide the functionality achieved by the high-level discrete signalingmechanism of FIG. 3A.

In addition, while the time domain approach to 4G and WiFi/B coexistencein FIG. 4 is described in connection with the 4G and WiFi/BT coexistencesystem 300 in FIG. 3A, the invention need not be so limited. Forexample, a similar approach may be implemented in the 4G and WiFi/BTcoexistence system 350 shown in FIG. 3B and in the 4G and WiFi/BTcoexistence system 370 shown in FIG. 3C.

Moreover, while the time domain approach to 4G and WiFi/BT coexistencein FIG. 4 applies to 4G and Bluetooth coexistence, it may also apply to4G and ZigBee coexistence, for example.

FIG. 5 is a flow diagram that illustrates exemplary steps for a timedomain approach to 4G and WiFi/BT coexistence, in accordance with anembodiment of the invention. Referring to FIG. 5, there is shown a flowchart 500 in which, at step 510, a 4G modem or other like device mayreceive a 4G downlink sub-frame. The 4G downlink sub-frame may beassociated with WiMAX communication, with TDD-LTE communication, and/orwith FDD-LTE, for example. The 4G modem may be, for example, one of themodems that support 4 G communication as described above with respect tothe 4G and WiFi/BT coexistence systems 300, 350, and 370.

At step 520, the 4G modem may disable WiFi transmission in a WiFi modembased on information in the 4G downlink sub-frame. For example, WiFitransmission may be disabled until the decoding of data in the 4Gdownlink sub-frame is completed. The WiFi transmission may be disabledby asserting a signal such as the RX_Active signal 334, for example. TheWiFi modem may be, for example, one of the modems that support WiFicommunication as described above with respect to the 4G and WiFi/BTcoexistence systems 300, 350, and 370. The disabling of the WiFitransmission may comprise disabling baseband operations in the WiFimodem and/or disabling a power amplifier in a WiFi front end such as theWiFi/BT front end 330.

At step 530, the 4G modem may enable the previously disabled WiFitransmission once the decoding of data in the 4G downlink sub-frame iscompleted. At step 540, a 4G up-link sub-frame may be received next bythe 4G modem. The WiFi transmission may remain enabled during the 4Guplink sub-frame received by the 4G modem at step 540.

At step 550, the 4G modem may transmit for at least a portion of the 4Guplink sub-frame and may provide an indication to the WiFi modem of theduration of such transmission. The WiFi modem may utilize suchinformation in carrying out CCA operations to determine whether energydetected in the medium is from the 4G transmission or from some othersource.

FIG. 6 is a flow diagram that illustrates exemplary steps to aggregateuplink transmissions in a 4G and WiFi/BT coexistence system, inaccordance with an embodiment of the invention. Referring to FIG. 6,there is shown a flow chart 600 in which, at step 610, a WiFi modem orother like device may generate an indication of pending WiFitransmission traffic and may send the indication to a 4G modem. The WiFimodern may be, for example, one of the modems that support WiFicommunication as described above with respect to the 4G and coexistencesystems 300, 350, and 370. Similarly, the 4G modern may be, for example,one of the moderns that support 4G communication as described above withrespect to the 4G and WiFi/BT coexistence systems 300, 350, and 370. Theindication may be for example, the WiFi_Data_Pending signal 338described with respect to FIG. 3A.

At step 620, the 4G modem, in response to such indication, may requestfrom a base station that the bandwidth allocation be modified to enableWiMAX communication through bursts of data. At step 630, based on thebandwidth allocation received from the base station, the 4G modem mayaggregate WiMAX transmission so that transmission occurs every N frames,for example. Fewer instances of WiMAX transmission may result in reducedWiFi interference that may allow the WiFi modem to address the backup inWiFi transmissions. At step 640, the WiFi modem may begin to transmitsome or all of the pending traffic.

FIG. 7 is a flow diagram that illustrates exemplary steps during WiMAXhandoff scanning in a 4G and WiFi/BT coexistence system, in accordancewith an embodiment of the invention. Referring to FIG. 7, there is showna flow chart 700 in which, at step 710, a 4G modem or other like devicemay enter into a handoff scanning mode. The 4G modem may be, forexample, one of the modems that support 4 G communication as describedabove with respect to the 4G and WiFi/BT coexistence systems 300, 350,and 370. In such scenario, signals from a current base station may bealready weak in relation to scan thresholds and disabling a WiFi modemduring handoff scanning may not be necessary. The WiFi modem may be, forexample, one of the modems that support WiFi communication as describedabove with respect to the 4G and WiFi/BT coexistence systems 300, 350,and 370.

At step 720, the 4G modem may scan N out of M frames received. In thisregard, the 4G modem may utilize at least the first 2 symbols receivedin each of the N frames scanned. In some embodiments of the invention,N=2 and M=20. At step 730, daring frame scanning, the 4G modem mayindicate to a WiFi modem to disregard any indication to disable WiFitransmission. When the 4G modem generates a signal such as the RX_Activesignal 334, and when such signal is asserted on the WiFi modem duringframe scanning, the 4G modem may generate some other indication to theWiFi modem to disregard the disabling of the WiFi transmission indicatedby the RX_Active signal 334. In some embodiments of the invention, the4G modem may deassert the RX_Active signal 334 during frame scanning.

The various steps described above with respect to FIGS. 5, 6, and 7 maybe applied to those instances in which Bluetooth communication isutilized instead of WiFi communication in coexistence with 4 Gcommunication.

Another embodiment of the invention may provide a non-transitory machineand/or computer readable storage and/or medium, having stored thereon, amachine code and/or a computer program having at least one code sectionexecutable by a machine and/or a computer, thereby causing the machineand/or computer to perform the steps as described herein for a timedomain approach to 4G WiMAX/LTE and WiFi coexistence.

Accordingly, the present invention may be realized in hardware,software, or a combination of hardware and software. The presentinvention may be realized in a centralized fashion in at least onecomputer system or in a distributed fashion where different elements maybe spread across several interconnected computer systems. Any kind ofcomputer system or other apparatus adapted for carrying out the methodsdescribed herein is suited. A typical combination of hardware andsoftware may be a general-purpose computer system with a computerprogram that, when being loaded and executed, controls the computersystem such that it carries out the methods described herein.

The present invention may also be embedded in a computer programproduct, which comprises all the features enabling the implementation ofthe methods described herein, and which when loaded in a computer systemis able to carry out these methods. Computer program in the presentcontext means any expression, in any language, code or notation, of aset of instructions intended to cause a system having an informationprocessing capability to perform a particular function either directlyor after either or both of the following: a) conversion, to anotherlanguage, code or notation; b) reproduction in a different materialform.

While the present invention has been described with reference to certainembodiments, it will be understood by those skilled in the art thatvarious changes may be made and equivalents may be substituted withoutdeparting from the scope of the present invention. In addition, manymodifications may be made to adapt a particular situation or material tothe teachings of the present invention without departing from its scope.Therefore, it is intended that the present invention not be limited tothe particular embodiment disclosed, but that the present invention willinclude all embodiments falling within the scope of the appended claims.

What is claimed is:
 1. A method comprising: receiving downlink mediumaccess protocol (MAP) information in a downlink sub-frame of a firstwireless protocol; disabling a transmission of a second wirelessprotocol during a portion of the downlink sub-frame based on thereceived downlink MAP information; enabling the disabled transmission ofthe second wireless protocol upon conclusion of decoding of availabledata within the downlink sub-frame; receiving uplink MAP information inthe downlink sub-frame of the first wireless protocol; generating asignal during an uplink sub-frame of the first wireless protocol basedon the received uplink MAP information; and controlling a clear channelassessment operation associated with the transmission of the secondwireless protocol based on the generated signal, wherein the receiving,disabling and enabling are performed by a communications device tothereby reduced interference between the first wireless protocol and thesecond wireless protocol, wherein the first wireless protocol is afourth generation (4G) protocol and the second wireless protocol is oneof WiFi and Bluetooth.
 2. The method of claim 1, wherein the uplink MAPinformation comprises an uplink burst profile and one or more physicallayer control messages.
 3. A method comprising: receiving downlinkmedium access protocol (MAP) information in a downlink sub-frame of afirst wireless protocol; disabling a transmission of a second wirelessprotocol during a portion of the downlink sub-frame based on thereceived downlink MAP information; and enabling, the disabledtransmission of the second wireless protocol upon conclusion of decodingof available data within the downlink sub-frame, wherein the receiving,disabling and enabling are performed by a communications device tothereby reduced interference between the first wireless protocol and thesecond wireless protocol.
 3. The method of claim 3, wherein the firstwireless protocol is one of Long Term Evolution (LTE), LTE Advanced,Worldwide Interoperability for Microwave Access (WiMAX) and WirelessMAN-Advanced, and the second wireless protocol is one of WiFi andBluetooth.
 4. The method of claim 3, wherein the first wireless protocolis a fourth generation (4G) protocol and the second wireless protocol isone of WiFi and Bluetooth.
 6. The method of claim 3, wherein thedownlink MAP information comprises a downlink burst profile and one ormore physical layer control messages.
 7. The method of claim 3, whereinthe disabling transmission of the second wireless protocol includesasserting an active receiver signal to thereby disable the secondwireless protocol, the active receiver signal indicating the receivingdownlink MAP information in the downlink sub-frame of the first wirelessprotocol.
 8. The method of claim 3, further comprising: generating anindication of pending transmission traffic of the second wirelessprotocol; requesting bandwidth allocation modification of the firstwireless protocol to a base station based on the generated indication;and if an indication is received that the requested bandwidth allocationmodification is granted, aggregating transmission traffic of the firstwireless protocol in accordance with a schedule associated with thegranted requested bandwidth allocation modification so that transmissionin the first wireless protocol occurs every N frames.
 9. The method ofclaim 3, further comprising: receiving downlink MAP information in adownlink sub-frame of, a next frame of the first wireless protocol; anddisabling transmission of the second wireless protocol during a portionof the downlink sub-frame of the next frame of the first wirelessprotocol based on received downlink MAP information in the downlinksub-frame of the next frame of the first wireless protocol.
 10. Themethod of claim 3, wherein the disabling of the transmission of thesecond wireless protocol includes: disabling a baseband operationassociated with the transmission of the second wireless protocol and aradio frequency front end power amplifier associated with thetransmission of the second wireless protocol.
 11. A communicationsdevice comprising: a first transceiver configured to receive downlinkmedium access protocol (MAP) information in a downlink sub-frame of afirst wireless protocol; and a second transceiver configured to disablea transmission of a second wireless protocol during a portion of thedownlink sub-frame based on the received downlink MAP information fromthe first transceiver, and to enable the disabled transmission of thesecond wireless protocol upon conclusion of decoding of available datawithin the downlink sub-frame.
 12. The communications device of claim11, wherein the first wireless protocol is one of Long Term Evolution(LTE), LTE Advanced, Worldwide Interoperability for Microwave Access(WiMAX) and Wireless MAN-Advanced, and the second wireless protocol isone of WiFi and Bluetooth.
 13. The communications device of claim 11,wherein the first wireless protocol is a fourth generation (4G) protocoland the second wireless protocol is one of WiFi and Bluetooth.
 14. Thecommunications device of claim 11, wherein the downlink MAP informationcomprises a downlink burst profile and one or more physical layercontrol messages.
 15. The communications device of claim 11, wherein thefirst transceiver is further configured to; receive uplink MAPinformation in the downlink sub-frame of the first wireless protocol,and generate a signal during an uplink sub-frame of the first wirelessprotocol based on the received uplink MAP information; and wherein thesecond transceiver is further configured to: control a clear channelassessment operation associated with the transmission of the secondwireless protocol based on the generated signal from the firsttransceiver.
 16. The communications device of claim 15, wherein theuplink MAP information comprises an uplink burst profile and one or morephysical layer control messages.
 17. The communications device of claim11, wherein the first transceiver is further configured to assert anactive receiver signal at the second transceiver to thereby disabletransmission of the second wireless protocol, the active receiver signalindicating the receiving downlink MAP information in the downlinksub-frame of the first wireless protocol.
 18. The communications deviceof claim 11, wherein the second transceiver is further configured to:generate an indication of pending transmission traffic of the secondwireless protocol; and wherein the first transceiver is furtherconfigured to: request bandwidth allocation modification of the firstwireless protocol to a base station based on the generated indicationfrom the second transceiver; and if an indication is received from thebase station that the requested bandwidth allocation modification isgranted, aggregate transmission traffic of the first wireless protocolin accordance with a schedule associated with the granted requestedbandwidth allocation modification so that transmission in the firstwireless protocol occurs every N frames.
 19. The communications deviceof claim 11, wherein the first transceiver is further configured to:receive downlink MAP information in a downlink sub-frame of a next frameof the first wireless protocol; and wherein the second transceiver isfurther configured to: disable transmission of the second wirelessprotocol during a portion of the downlink sub-frame of the next frame ofthe first wireless protocol based on received downlink MAP informationin the downlink sub-frame of the next frame of the first wirelessprotocol from the first transceiver.
 20. The communications device ofclaim 11, wherein the second transceiver is further configured to:disable a baseband operation associated with the transmission of thesecond wireless protocol and disable a radio frequency front end poweramplifier associated with the transmission of the second wirelessprotocol.